Adult Echocardiography Practice Exam

In m-mode, the arrow typically demonstrates which structure?

1. Posterior wall

2. Papillary muscle

3. Trabeculae carnae

4. Left ventricle

The correct answer is: Papillary muscle

In m-mode echocardiography, the arrow typically indicates a specific structure by highlighting the movement and positioning of that part of the heart over time. In this context, when identifying what is represented by the arrow, the papillary muscle is often displayed prominently. The papillary muscles are attached to the heart's ventricles via the chordae tendineae, and they play a crucial role in the functioning of the mitral and tricuspid valves by preventing them from prolapsing into the atria during ventricular contraction. In the m-mode view, the prominent echogenicity of the papillary muscles, along with their distinct motion during the cardiac cycle, makes them easily identifiable. M-mode echocardiography allows for a detailed assessment of the heart's structures and their motion, and the papillary muscles are typically seen as they contract and relax alongside the left ventricle, providing vital information about cardiac function and valve mechanics. Understanding their visualization is critical for interpreting overall left ventricular performance and valvular integrity.